Watchmaker&#39;s tool and method



jan.. 28, 1936. f E M* RlCHARDSON 2,029,194

WATGHMAKERS TooL AND METHOD Filed April 3, 1934 Ewen/eff @man Patented Jan. 28, 1936 UNED STATES gezant TENT GFFICE 24 Claims.

The present invention relates to a method and apparatus for forming a pivot at the end of the staff of a balance wheel of a watch or the like. While the method and apparatus are described in connection with a balance staff, it is not meant to restrict the invention to this particular kind of staff, as obviously the method may be practiced and the apparatus used in connection with other stairs which are used in the construction of watches or clocks and the like.

In the drawing, which is illustrative and in no manner restrictive, like numerals refer to like parts throughout the several views,

Figure l is a longitudinal vertical sectional view of the device, showing the chuck jaws in open position;

Figure 2 is a side elevational view of the device;

Figure 3 is a transverse vertical sectional View along the line 3 3 of Figure 2;

Figure 4 is an end view of the chuck, showing the jaws of the same in open position;

Figure 5 is a transverse vertical sectional view on the line 5 5 of Figure 1;

Figures 6 and 7 are perspective views of the chuck operating cam members showing the same assembled with the operating handles; and

Figure 8 is a view of the chuck operating cam members in assembled position.

In repairing a broken pivot of a balance wheel staff, the conventional procedure has been to replace the broken balance stair with a new one. Referring to Figure l, the balance wheel assembly is shown as comprising a balance staii 2U which is secured centrally of a at diametric spoke 2l of the balance wheel 22. The balance staff has relatively small end portions, and a relatively large central hub portion, the hub being somewhat larger, as at 23, on one side of the balance wheel spoke than on the other. When o the balance wheel is assembled, the staff is inserted in a central aperture in the spoke until the hub portion 23 abuts against the spoke, and then suitable attaching means are provided as at 24 to secure the balance wheel spoke to the hub of the staff.

In replacing a balance staff which has a broken pivot, it is necessary to loosen the fastening means at 2d to permit the removal of the broken staff, substitute the new staff, and replace the fastening means at 2d. It will be seen that if this procedure is followed, it will necessitate a considerable number of steps in completing the repair. That is, the new balance staff will necessarily have to be made to fit the old balance wheel and hair spring collar, and after it has been secured within the spoke of the old balance wheel, it will be necessary to turn down and true both ends of the new staff to iit the bearings into which they are to be placed.

In order to avoid this procedure which has heretofore been followed, I have evolved the method and devised the apparatus disclosed herein, which makes possible the repairing of a staff having a broken pivot without removing the sta-1T from the balance wheel. In carrying out this method, I replace thev broken end of the balance stal by drawing out the stock of the broken end to a suiiicient extent to permit the formation of a new pivot.

Referring to Figure 1, the end 26 of the balance stad is shown in position between the jaws 2l of a chuck member. Although the end 26 of the balance staff is shown projecting into the jaws 27, it is obvious that the opposite end of the stai may be operated upon by simply reversing the balance staff in the supports. As shown in Figure 4, the chuck member is provided with three jaws which are formed by the three radial slits or cuts 28 which are substantially one hundred and twenty (120) degrees apart, and extend a substantial distance along the length of the chuck as shown in Figure l. Near the axis of the chuck, the slits are somewhat more narrow so that at the centre 29, an opening into the interior of the chuck is left which is only of sufficient size to permit a small object to be inserted, such as the end of a balance wheel staiT. The outer surfaces of the chuck jaws 2'! iare outwardly as at 30 (Figure l) to fit the conical socket 3l in one of the chuck cam members 36. The chuck extends through the chuck cam member 36, which will be later described, and terminates at its rear end in an exteriorly screw threaded section 33, said section being for cooperation with the interior screw threads of a chuck retaining nut 34. The retaining nut 34 has a shoulder 34' at the inner end of its screw threaded section, which shoulder abuts against the inner end oi the chuck to prevent retaining nut 34 from binding against the chuck operating cam members.

It will be noted that the chuck has a hollow bore 35, and that when the chuck is drawn inwardly, the jaws 2l will be compressed within the socket 3|. Furthermore, when the force tending to draw the chuck inwardly is removed, the jaws 2'! will spring to their original, or open position.

The chuck operating mechanism comprises a pair of cam members, the cams being sections of CTI jection 43 on cammeinber'llil, projection 43 beingY adapted to be positioned in recess 59 when the parts are assembled, to permit cam surface 4l to engage corresponding surface 31, and surface 42 to engage corresponding surface V33. It will be noted that the arc of recess 55 is greater than the arc of projection 45, thus permitting a limited i spiral movement or" the latter within the former as the chuck is operated. The cam members 36 and i6 are shownV in assembled position inFigure .L

8. Cam member'46 is secured within retaining sleeve 45, which sleeve is also adapted to it over extension 59 ofthe canfmember' 36 in order that the plate may adjustably secured to the same. The position ci the aperture 56 is such that, when the ila-nge 5l is screwed onto the threaded extension 59 ofthe careY 35, thelaperture 56 will be in alignment with the central opening 29 between the chuck jaws 27. 'Y a In Figure 1, it will be seen that a portion oi the cani member S5 extends to the outer surface of the lassembled device at the'inner end of the cam member sleeve 45, as at 65, and this circular extension is suitably calibrated as at (Figure 2) to provide an indicating scale. To cooperate l with said scale, a pointer or mark 52 is: made in the other cam member 36 when the chuck operating mechanism'is assembled, as shown iii-Figure An operating handle A is secured to the sleeve 55, and is provided with an extension 4lY which passes through and is secured to the cam member 40. Cam member is likewise provided with an operating handle B. Within cam member 35, and integral therewith, is a cylinder 43 which is provided with a central longitudinal bore 45 for the reception of the chuck.

It will be apparent from Figures 6 and 7 that when the chuck operating cam members are assembled and when the handles A and B are moved together, the cooperating cam surfaces will cause cam member 46 to be moved outwardly with respect to cam member 36. Referring to Figure 1, it will be noted that the chuck retaining nut 34, when it is screwed up upon the threaded portion 33 of the chuck, will be flush against the rear face of the cam member 46, as shown at 5i. Conse- Y quently, when the arms A and B are brought to- 'getheig the outward movement of cam member 46 will forcerthe chuck retaining nut 35 outwardly, which in turn will draw the chuck jaws 21 into their conical socket 3l, thus compressing the chuck jaws to operate upon the end of the balance stai 26.

In Figures 1 and 5, it will be noted that the exterior surface of the chuck is provided with a key-way 52. 'I'his key-way is provided for cooperation with the projection 53 extending into the bore 49 of the cylinder 48. By this arrangement, the chuck is retained against rotation, while at the same time, the cooperation of projection 53 with key-way 52 will permit longitudinal movement of the chuck with respect to the cylinder 48 through which it passes.

In order to position the balance wheel with its staff with respect to lthe chuck, a supporting means is provided, said means comprising a retaining plate 55, and a member 55 for urging the balance staff toward the chuck. As shown in Figures 1 and the retaining plate is provided with a central aperture 55 through which the balance staff may pass, and the plate also has a portion of its surface cut away as at 51' in order that the operation of the chuck jaws may be observed.

Surrounding the aperture 56, the retaining plate has an outwardly extending boss 56. This boss insures thatvthe work, such as a VbalanceV wheel, will notI be injured by being forced up against the retaining plate 54 by the urging member 55. By this arrangement strains in either direction will be taken up at the hub of the wheel.

The retaining plate 54 has integral therewith a flange 51, said flange being interioriy screwthreaded-as at 58 to screw onto the threaded the outer surface of the retaining plate ange 5l. Similarly, a mark or pointer 55Y may be provided on the outside surface of the cam member sleeve 45 to indicate on scale 6l the degree of opening and closing of the jaws. Y'

Extending outwardlyT from the edge of the retaining plate 54 is a hcrizontalsupporting member 65, said member terminating in a vertical extension 66 which is provided with a bearing 61 whose axis is in alignment with the center of aperture 56 in plate 54. The rod 55 is carried in bearing 61 and has at the outer end thereof a knurled handle portion 68, and is provided, nearV its inner end, with a collar 69. Between the outer side of collar 69 and the vertical supporting member 66, a spring 16 is arranged surrounding the rod 55, said spring normally urging the rod toward the retaining plate. The inner end of the rod 55 is bored out as at H in order to receive oneY end ci the balance sta. 4

When it is desired to repair the broken end of a balance wheel staff, the same is assembled in the supporting mechanism with the unbroken end of the staff extending into the aperture 1l, while the broken end ofthe stair extends through the aperture 56 in the plate 54 in position to be operated upon by the chuck jaws. The spring 16 acting against collar 69 rthen tends tc press the balance staff hub against the edges of the aperture 56 and the plate 54, and in this manner holds the broken end 26 of the balance stai in nalignment with the opening 29 between the jaws of the chuck member 21. The boss 56 maintains the balance wheel aV suiicient distance from the plate 54 to preclude the possibility of injury to the wheel. Y I have found that, to secure the desired elongation of the brokenV end of the balanc-e staff, the broken end should be inserted within the open jaws of the chuck a distance of 12/1060 in order to securel an elongation of 1/1060" when the chuck is operated. In adjusting the position of the balance staff within the jaws, I have found that it is desirable to rst close the jaws and then screw the flange 57 onto the cam member extension 59, thus moving the plate 54 inwardly untii the broken end of the balance staff abuts against the outer'surface of theV jaws 2l, the end of the balance Ystaff not being permitted to enterV the opening 25 between thejaws by reason of the fact that said jaws are in closed posi,- tion. After this procedure has been followed, the jaws may be opened, and the flange 5'! may then be screwed further onto the cam member extension 59 until the desired length of the balance staff is inserted into the opening 29 between the jaws. This distance will be indicated by the movement of the pointer or mark 62 on the iiange 51 with respect to the scale 5i on the circular ex tension 66 of the cam .member 35. While Ihave found that it is desirable to move the end of, the

balance stair into the jaws a distance of 12/1000, it is obvious that any degree of insertion may be used to accomplish the desired result with the particular kind and shape of staff being operated upon.

After the end of the balance staff has thus been inserted into the open jaws of the chuck as shown in Figure l, the handles A. and B are pressed tog-ether, and the cooperative movement of the cam surfaces ii and t2' will cause an outward movement' of the cam member li with respect to cam member 35, which movement will be imparted to the chuck retaining nut @d to thus draw the chuck jaws 2l within their conical cavity 3! in order to compress the jaws. As the chuck jaws 2 are compressed, obviously they will also be moved inwardly, and by these movements the end of the balance stati 26 will be compressed and drawn out to form an elongated portion, which portion will make up for the length of stati lost, due to the breakage. The elongated end may be somewhat tapered toward its end and will thus be roughly preformed for the subsequent steps or" the method. When the handles A and B are pressed together, cam member 46 will rotate with respect to cam member 36, and cam member sleeve 45 will thus move with respect to scale 6|. The degree of closing of the jaws, and thus the amount of elongation of the staff may be thus controlled by the handles A and B, and indicated on the scale 6l, by the pointer 63 on sleeve 45.

After the broken end of the balance stair" has thus been drawn out to form an elongated tapered end, the end may be subjected to turning and polishing operations to form the end into the desired size and shape to t its bearings.

From the method described above, it will be obvious that in repairing a broken balance staff, only two operations will be necessary, namely, the drawing out of the broken end of the staff as discussed above, and the truing and polishing of the elongated end to t its bearing. Thus, the broken end of the stair" may be renewed without removing the staff from the balance wheel. Obviously, the practice of the method and the use of the apparatus will result in a pronounced saving in time and materials.

Such changes of the construction and method herein disclosed as amount only to mechanical skill may be made without departing from the range of the invention.

I claimrl. The method of forming a pivot at the end of a staff which comprises drawing out the end of the stair, and turning the drawn-out end to proper size and shape to t its bearing.

2. The method of forming a pivot at the end of a staff which comprises drawing out the end of the stai to form an elongated and tapered end, and turning said end to proper size and shape to fit its bearing.

3. The method of forming a pivot at the end of a stair which comprises subjecting the end of the stai to a compressing and pulling force in order to elongated the same, and turning the elongated end to proper size and shape to t its bearing.

4. The method of forming a pivot at the end of a stair which comprises compressing the end of the stair to elongate the same, and turning the elongated end to proper size and shape to t its bearing.

5. The method of forming a pivot at the end cf a stai which comprises compressing the end ofthe stair to form an elongated and tapered end, and turning said end to proper size and shape to t its bearing.

6. In a device for forming a pivot at the end of a stair, the combination of means for supporting the stai, and means for drawing out the end of the staff to elongate the same.

7. In a device for forming a pivot at the end or a staff, the combination of means for supporting the stati, and means for compressing the end of the staff to elongate the same.

8. In a device for forming a pivot at the end of a stair, the combination of means for supporting the staff, and means for compressing and drawing out the end of the stair to elongate the same.

9. In a device for forming a pivot at the end of a stai, means for supporting the staff, means for drawing out the end of the staff, and means for relatively adjusting said supporting means and said drawing-out means'with respect to one another.

10. In a device for forming a pivot at the end of a stai, means for supporting the staff, means for drawing out the end of the stan to elongate the same, and means for relatively adjusting said supporting means and said drawing-out means with respect to one another to determine the extent of the elongation of the shaft.

ll. In a device for forming a pivot at the end of a staff, means for supporting the stai, means for drawing out the end of the staff, means for relatively adjusting said supporting means and said drawing-out means with respect to one another, and means for indicating said adjustment.

l2. In a device for forming a pivot at the end of a stair, a retaining member, a member located on one side of said retaining member for urging the staff toward Said retaining member, means for permitting the end of the staff to project beyond said retaining member, and means on the opposite side of said retaining member for drawing out the projecting end of the staff.

13. In a device for forming a pivot at the end of a stai, a member having an aperture therein, means on one side of said member for supporting the staff with one of its ends projecting through the aperture in said member, and means on the opposite side of said member for drawing out the projecting end of the stair.

14. In a device for forming a pivot at the end of a stai carrying a wheel, a retaining member having an aperture therein, a member for urging the wheel against said retaining member with one of the ends of the stair projecting through the aperture in said retaining member, said urging member being located on one side of said retaining member, and means on the opposite side of the retaining member for drawing out the projecting end of the staff.

l5. In a device for forming a pivot at the end of a staff, a chuck for drawing out the end of the stair to elongate the same, and a support for said staff, said chuck and support being relatively adjustable with respect to one another.

16. In a device for forming a pivot at the end of a stai, a chuck for drawing out the end of the staff to elongate the same, and a support for said staff, said chuck and support being relatively adjustable with respect to one another and having means for indicating said adjustment.

1'7. In a device for forming a pivot at the end of a stair, the combination of means for supporting the stai, and a chuck for drawing out the end of the stai to elongate the same.

18. In a device for forming a pivot at the end of a staff, the combination of means for supporting the stai, and a chuck for compressing the end of the staff to elongate the Same.

19. In a device for forming a pivot at the end of a stai, the combination of means for supporting the stai, and a chuck for compressing and drawing out the end of the staff to elongate the same.

20. In a device for forming a pivot at the end of a stai, the combination of means for supporting the staff, means for drawing out the end of the stai to elongate the same, and means associated with said drawing out means for indicating the extent of elongation of said staff.

21. In a device for forming a pivot at the end of a stai, a chuck, means for supporting the sta with the end thereof extending between the jaws of said chuck, and means for compressing said jaws onto the end of the staff to draw out theV same.

22. In a device for forming a pivot at the end of a staff, a chuck, means for supporting the staff with the end thereof extending between the 5 jaws of said chuck, and means for compressing said jaws and moving them longitudinally and toward the extending end of said staff to draw out the same. Y

23. The method of renewing a broken pivot at 1() the end of a stai which comprises elongating the staff, and turning the end of the stai to proper size and shape to t its bearing. Y

24. The method of renewing a broken pivot at the end 4of a staff which comprises compressing 15 the staff'to elongate the same, and turning the end of the stai to proper size and shape to fit its bearing.

EUGENE MYRIAN RICHARDSON. 

